Claude Code adds prompt-time config commands and new macOS sandbox controls

Anthropic shipped an update to Claude Code adding flexible prompt-time configuration commands that give developers finer control over the coding agent's behavior on the fly, along with new macOS sandbox and notification controls aimed at improving security and the desktop experience. The release also targets a smoother core experience with faster startup times and more efficient operation.

The macOS sandbox controls are the most security-relevant addition: as agentic coding tools gain broader filesystem and execution access, containment becomes essential — a theme echoing DeepMind's 'AI Control framework' this week. Prompt-time config lets users adjust agent permissions and behavior per-session rather than through static global settings.

The update lands at a delicate moment for Anthropic's coding franchise. Microsoft is reportedly migrating its own developers off Claude Code to an in-house Copilot CLI for cost reasons, and OpenAI just won a company-wide Samsung Codex deployment — making continuous Claude Code polish important for retention. Separately, Claude Code lead Boris Cherny highlighted a creative use case: deciphering Linear A, a 3,500-year-old Cretan script (2,312 likes).

Watch next: how the new controls affect adoption amid enterprise cost-cutting, and whether Anthropic can differentiate Claude Code on security and control as competitors close the capability gap.